To be an effective software tester, one needs to possess a combination of technical and non-technical skills. This includes having a thorough understanding of business situations, being able to analyze and map out complex problems, and having a logical approach to testing. Effective communication and reporting are also crucial, as well as the ability to understand code and automate processes where possible. Additionally, knowledge of software development life cycles, project management, and latest web and mobile technology trends is essential. Testers should be able to work collaboratively with developers and other stakeholders, build trust and rapport, and stay up-to-date with new technologies through continuous learning. Furthermore, they need to possess skills such as cross-browser testing, front-end communication, and the ability to plan and document their testing process. Ultimately, a software tester's unique perspective and problem-solving skills are also critical to identifying critical issues quickly.